Work-support-controlling mechanism



APPLICATION FILED FEB. 9, 1915.

Patented Oct. 26, 1920.

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UNITED STATES.

PATE-Nr oFFicE.

GEORGE GODDU, GF WINCHESTER, MASSACHUSETTS, ASSIGNOR, BYMESNE VASSIGrN- MENTS, TO UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JER-v SEY, A CORPORATION OF NE'W JERSEY.

WORK-SUPPORT-CONTROLLING MECHANISM.

Application filed February 9, 1915.

To all whom t may 00a/cera.'

Be it known that l, GEORGE GoDDU, a citizen of the United States, residing at lVinchester, in the county of Middlesex and State Aof Massachusetts, have invented certain Improvements in VVork-Support-Controlling Mechanism, of which the following description, in connection with the accompanying drawings, 'is a specification, like reference characters on the drawings indicating like parts in the several figures.

This invention relates to work supports and to work support controlling mechanisms and is herein shown as embodied in a work support and its controlling mechanism of the type which is particularly adapted for use in machines for inserting fastenings in boots or shoes. It will be understood, however, that the invention is not restricted to the illustrated embodiment or to the illustrated'uses.

The machine in which the invention is herein shown as incorporated is of the type which employs an awl to form a fastening receivine` opening in the work, the awl then operating to feed the'work into position to have the fastening inserted in said opening. In such machines it is important that the work be firmly supported, both at the time the awl is forced into the work to form the fastening receiving opening and at the time the fastening is driven. Between these operations it is desirable that the pressure upon the work be diminished or altogether relieved in order that the awl may feed the work easily and without danger of injury to the awl, such as bending or breaking.

Machines of the type in which the inven-V tion is shown as incorporated are operated at comparatively high speeds; that is, at speeds which ran from 410() to 60() fastening inserting operations per minute.v ItV is essential, therefore, that Vthe control of the work support in a machine of this type'be substantially positive in order to insure the proper coperation between the work support and the fastening inserting mechanism. To provide for the quick accommodation of the work support to variations in the thickness of the work and at the same time to accelerate the return of the work support to its supporting position after the work feeding operation, and sometimes to afford a strong yieldin@ support for the fastening Specification of Letters Patent.

Patented oet. 26, 1920.

Serial No. 7,083.

normally in work rclamping position, a

treadle being connected to the work support to depress it against the spring when it is desired to remove the workI or to place work upon the work support and a secondtreadle being provided to control the starting and stopping of the machine. Such work support operating and controlling mechanism is shown and described in United States Letters Patent to L. Goddu, No; 265,227, September 26, 1882, and an ob] ect of the present invention is to improve the construction and to simplify the operation of work supports of the general Vtype disclosed in said Letters Patent. To this end the invention aims to provide for` the control, from a single treadle, of the movement of the workisupport between work receiving position and work clamping4 position and the starting and stopping of the machine, without sacrificing any of the advantages of firm support at proper times in the operation of the machine which have made the earlier construction so satisfactory, as attested by its common use.

More particularly the inventionV aims to provide work support controlling 'mechanism of the single treadle type which can readily be applied to, or incorporated in,

machines already in use. Y

An important feature of the invention iS the provision, in work support controlling mechanism of the single treadle type, of novel means controlled from said-treadle for preventing premature lowering of the work support. K n

In accordance with another feature of the invention, the treadle controlled means for preventing prematureflowering of the horn is constructed and arranged to provide a rigid support for the work support when it is in its operative position and, preferably and as shown, to be moved into its supporting position after the work supportihas been raised into final work clamping position but before the machine is started.

@ther important features and objects of the invention will. appear from the following description and claims when considered in connection with the accompanying drawings.

In the accompanying drawings,

Figure l shows in side elevation, with parts broken away to make clearer the construction of parts otherwise concealed, a machine oi` the type illustrated in United States Letters Patent to L. Goddu, No. 490,624, January 24, 1893, having incorporated therein the work support controlling mechanism of the present invention, the parts beingin inoperative position;

Fig. 2 is a detail elevation showing the parts in operative position.

The mechanism in the head of the machine for controlling the starting and stopping` of the machine, and the mechanism in the head of the machine for operating the connections to the work support by which the work support is depressed for the feeding of the work, are substantially identical with those shown and described in Letters Patent No. 490,624, hereinabove referred to, the wedge C3 at the upper end of a rod C4, the cam disk CG having a beveled periphery engaged by a brake B1 and receiving in a cam groove in its face roller upon the lever C7 to which is connected the rod C8 by which the pawl carrying slide Z2 .is operated, being substantially the same as the parts indicated by corresponding reference char cters in said Letters Patent, the pawl carrying slide d2 being shown and described in the earlier Letters Patent hereinabove referred to, No. 265,227. is in said earlier Letters Patent, the slide d2 carries a pawl rl adapted to engage one of the teeth d5 of a ratchet slide which is connected by a rod ZG to a lever C9 having conne tions at its other end to the work support. whereby the work support may be depressed during the work feeding operation, the pawl Z being thrown out oil engagement with the ratchet teeth Z5 upon the return movement or" the slide d2 by engagement with the cam block d? and being yieldingly maintained in engagement with the ratchet teeth by a spring plunger d8. T he parts thus `far described, with the exception of the rods (ZG and C4, are substantially identical with the parts indicated by the corresponding reference characters in said Letters Patent No. 265,227.

To facilitate the removal of the work from the work support and the placing of the work upon the work support the invention aims to provide means for causing the work support to move into work receiving position when the machine stops and for moving it again into work clamping position bei-ore the machine starts, this means being arranged to be controlled from a sin- `gle treadle. rlihe work support, which is herein shown as of the horn type, comprises 2 through breakable connections now to be described.

The horn 2 is carried upon a horn post 14 arranged to slide vertically in a guide 'i6 formed upon the machine frame, the horn post 14 being connected at its lower end, by means of a rod 18, to a slide 20 guided in an opening in a horizontal portion 22 of the machine base, the slide 20 being arranged to move vertically in said opening but being limited in its downward movement by a stop washer 24 confined against the upper end of said slide by a nut 26 upon the rod 18. The lever C is fulcrumed upon a cross shaft 28 carried by depending ears 30 in the machine base, and also ulcrumed upon this cross shaft is a treadle lever 32 which is pivotally connected at its rear end to a rod 34 guided in a guideway 36 in which the lower end of the rod C4 is guided, these rods having their ends normally separated when the-machine is at rest, the spring 38, which surrounds said rod and is confined between the rear end o* the treadle lever 32 and the lower part orn that portion of the machine frame in which the guide 36 is formed, tending to keep the forward end of the treadle lever 32 raised and the rear end depressed, thus maintaining the upper end of the rod 34 out of engagement with the lower end oi the rod C4. A light spring 40, confined between a collar 42 upon the rod Ct and the upper end of the bracket in which the guide 36 is formed, prevents the rod U4 from dropping, under the action of gravity, into engagement with the rod 34. The treadle lever 32 has formed upon it a depending arm 44 which makes of the treadle lever a bell crank by which a toggle may be operated to raise the'horn 2 into work supporting position before the machine is started, the breaking of the toggle after the treadle has been released to stop the machine operating to lower the horn into work receiving position.

The illustrated toggle mechanism comprises a link 46 which. straddles the slide 20 and has a pivotal connection 48 with said slide, the ends of said pivot 4S being guided in elongated slots 50 in the slide 20 and normally vpositioned to bear against the slide 20 at the upper ends of the slots 50. The forked lower link 54 ofthe toggle is pivotally connected to the upper link at `with the lever C9 and has a further pivotal connection through a link 5"? with the arm 44 of the treadle lever 32. A stop 59 eX-V tending between the two parts oli the lilik 54 brings up against the side face ot an extensionTO upon the slide 2O when the toggle has been moved into straightened, orl slightly past straightened position, in order to prevent the toggle from breaking too far in the other direction. v

To provide means for affording a more rigid support for the horn and also ineans for preventing the horn from dropping before the machine has Completed its operation upon the work, a stop-member 56 is pivoted at 58 to the lever C and is located between the two sides of the link 54. A pin 6() carried by said stop member extends into the slots 62 in the link 54 and limits the relative movement about the axis 58 of the link 54 and the stop member 56. A spring 64 connected to the link 54 and engaging the pin 60 tends to keep the link 54 and stop member 56 in the relative positions shown in Fig. l. )The stop member 56 has a stop facey 66 at its upper end adapted to coperate with a similarstop face 68 upon the lower end of the extension member 70 of the slide 20, the side oi said member 56 adjacent to the extension 70 in Fig. l of the drawings being adapted to cooperate with a lateral stop 78 upon the extension member 70. To permit relative movement oit the Vend faces 66 and 68 of the parts 56 and 70 into and out of engagement without binding as the member 56 turns about its pivot 58 the end face 66 of the member 56 is slightly inclined, and` the end face 68 of the extension 70 is correspondingly inclined.

The stop recited in combination with the work support in certain of the claims at the end ot this specification, finds its specific embodiment in the illustrative machine in the stop member 56. It is to be understood, however, that the term stop-nas used in these claims covers any device arranged to b5" interposed in the path ot thework support to act by its presence as an destruction to movement ot the work support. Then interposed below the work support, such a stop device serves as a support `for the work support. Y

The operation of the mechanism ythus liar described is as follows: The parts being in the position s hown in Fig. l, the-operator places the work upon the horn 2 and then depresses the treadle v82 Causing .it-to lrock in a clockwise direction about the tulcraim shaft 28 (see Fig. l). During the iirst part of the movement of the treadle the toggle link 54 will be rocked about the pivot 58 upon the forward end of the lever C9, thus tending to straighten Vthe toggle to raise the slide 20 until the horn 2 clamps the work against the foot plate or work abutment 4. lVhen the kwork is thus clamped further movement of the toggle toward straightened position will depress the pivot 58, thus raising the rear end oit the lever C and. compressing the spring 6 between the collar l2 and the post 8. During this straightening 'movement of the toggleand until the upper end i'ace 66 of the member 56 has been moved below the lower end face 68 of the eX- tension 70, or vice versa, there will be a relative movement of the member 56 and thetoggle link 54 about the pivot 58 against the tension of the spring 64. When the toggle is substantially in straightened position the pivots 58 and 48 will be separated sufficiently so that the end faces 66 and 68 will have passed by each other, thus permitting the sprino' 64 to move the member 56, the pin 60 or which is now near the left hand end of the slot 62, in a clockwise direction about the pivot 58 to bring the end face 66 beneath the end face 68, the side of the member 56 abutting against the stop 73 upon the extension 70. Further movement of the treadle operates to break the toggle slightly to the other side and to draw the end faces 66 and 68 into engagement with each other, the stop 59, which abuts against the side of the extension 70, serving to limit the breaking movement of the toggle upon this side. -During the last part of the movement of the treadle the upper end of the rod 84 has engaged the lower end of the rod C? and raised the wedge C3 into clutch operating position thus starting the machine after the work support has been brought into work clamping position, springV pressure has been applied to the work support and a positive rigid connection between the lever C and the work support has been eil'ected.,

The machine having been started the awl enters the work in the usual manner and is then moved to feed vthe work over the rhorn 2, but before this feeding movement begins the horn 2 is depressed by the horn release or work support rele ng mechanism hereinabove described. The operation of this merhanism is substantially identical with that describer in Letters Patent No. 265,227, hereinabove referred to. n

The required number oi" operations having vbeen performed uponthework the operator releases the t'readle 32` and the spring 88 immediately rocks it ina counter-.clockwise dirertion about the ulcrum shaft 28, the'iirst part of the movement of the treadle serving to move the upper end of the' rod 34 out ofengagement with the lower end of the rod C, thus permitting the wedge C3 to move out oi clutch operating position, whereupon the machine stops at the end of a complete operation, as more fully set forth in Letters Patent No. 490,624, hereinabove referred to.

Further movement of the treadle serves to break the toggle into the position shown in Fig. l, the first part of the movement of the treadle slightly depressing the pivot 5S and bringing the toggle into its straightened position and also eti'ecting a relative morement of the link 54 and the member 56 so that the pin 60 is brought 'into the right hand end of the slot 62, whereupon, during the further breaking movement of the toggle, the link 54 and the member 56 move together, the end face 66 oi said member being moved out from its position under the end face 68 of the extension 70, by the engagement of the right hand end of the slot 62 with the pin 60 on the member 56, thus permitting the horn to drop as the .treadle rises and the toggle is broken into the position shown in F ig. l. During this further breaking movement of the toggle, the toggle link 46 moves freely downwardly relatively to the slide 2O in the slots 50, thus permitting the withdrawing movement of the member 56 by the toggle link 54, the spring 38 being sutiiciently strong to overcome the pressure upon the end face 66 caused by the weight of the horn, and the iuclinations of the faces 66 and 68 preventing interlocking or binding of those faces. It will be seen that the slot 62 provides lost motion to prevent the horn from being low ered until the treadle has moved sutliciently to throw the wedge C3 into clutch releasing position so as to insure stopping of the machine before the horn is lowered.

To prevent the expansion of the spring 6 to the limit when the toggle is broken and the work support is lowered and also to prevent interference with the lowering operation, a stop 74 is provided upon the lever C9, this stop being threaded through a cross piece 72 which straddles the leg 71 of the machine base and engages a stop surface 75 formed upon said leg.

It will be noted that the lost motion between the rods 84 and C4 is sufficient to permit the raising of the work support by the straightening of the toggle 46, 54, and the interposition of the stop 56, before said rods engage and that the further lost motion provided by the pin and slot connection between the stop 56 and the link 54 issuiiicient to allow the clutch to be operated to start the machine after the work support is in work supporting position.

It will also be noted that the link 57 is in such relation to the lever C9 that it does not interfere with the intermittent depression of the work support for the feeding of the work between the successive operations thereon. I' d Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. In a machine of the class described, a work abutment, a work support movable relatively to said abutment to clamp the work between the work support and the abutment, means for raising said work support to apply final work clamping pressure, starting and stopping means, a single treadle for operating said work support raising means and said starting and stopping means to perform the operations described, a stop for preventing premature lowering of said work support, and means whereby said stop is controlled from said treadle.

2. In a machine of the class described, a stationary work abutment, a work support, a treadle, means operated by said treadle for raising and lowering` said work support between a work receiving position and a final work clamping position, positive connections between said treadle and said rais ing and loweringmeans, a stop for preventing premature lowering of said work support, and lost motion connections between said treadle and said stop.

3. In a machine of the class described, a work support, an abutment between which and said work support the work is clamped, means for raising said work support to apply iinal work clamping pressure, clutch operating means, a treadle, positive connections between said work support raising means and said treadle for operating said means, lost motion connections between said treadle and said clutch operating means, constructed and arranged to cause said work support to be fully raised before the machine is started, a stop for preventing premature lowering of said work support, and lost motion connections between said treadle and said stop.

4. In a machine of the class described, a work support, a spring, work support raising means constructed to apply the pressure of said spring to said work support, a treadle, positive connections between said treadle and said raising means for operating said raising means, a stop for preventing premature lowering of said work support, and 10st motion connections between said treadle and said stop.

5. In a machine of the class described, a work support, starting and stopping means comprising a treadle, a toggle for raising and lowering said work support, positive connections between said toggle and said treadle, a stop for preventing premature lowering of said work support, and lost motion connections between said stop and said treadle.

6. In a machine of the class described, a work support, starting and stopping means comprising a treadle, a toggle for raising and lowering said work support, meansfor positively straightening and breaking said toggle, a stop :tor preventing prematurd lowering of said work support, and lost `inotion connections between said stop and said treadle for operating said stop.

7. In a machine of the class described, a work support, a toggle through which said work support is raised and lowered, a stop for preventing premature lowering or' said work support, and lostk motion connections between said toggle and said stop or op erating said stop.

8. In a machine of the class described, a work support, a spring, a pair of toggle members for bringing spring pressure to bear upon said work support, and means acting when said toggle is straightened to establish a supporting connection independent of the toggle members between the pointsconnected by said toggle.

9. In a machine of the class described, a work support, starting and stopping means comprising a treadle, connections between said work support and said treadle constructed and arranged to cause the work sup port to be raisedv to apply final work clamp'- ing pressure before the machine is started,

and means also operated from said treadle' for locking said work support in said work supporting position.

10. In a machine of the class described, aV

work" support movable between work re-l ceiving position andwork supporting position, a toggle arranged to be straightened toV effect the movement of the Ywork support into supporting position and to be broken to permit the movement into receiving position, means ior straightening and breaking said toggle, and means independentl or the members of the toggle for establishing a work supporting connection between'the points connected by said toggle.

11. In a machine or' the class described, a work support, starting and stopping means comprising a treadle, a toggle for raisingV and lowering said work support, positive connections between said-'treadle'and said toggle, a spring arranged to be compressed by the straightening of said toggle to bring spring pressure to bear upon the work support, a stop for preventing premature removal or" said spring pressure, and lost mo-V tion connections between said stop'and said treadle.

12. In a machine of the class described, a work support, a spring for inaintainingjsaid work support in Voperativefposition, means for intermittently depressing said work support to permit the Work to be fed there.` over, connections betweenl said Ywork support and saidv depressing means comprising a toggle,f and means yfor maintaining the means comprising parts connected by said'toggle in extended relation. n e i 13. In a machine ofl theclass described, the combination with a work support, and means Yfor intermittently depressing said work support, of means for moving said work support from work receiving position to work clamping position before the machine is started comprising a treadle 0perated toggle, means for maintaining in eX tended relation the partsvconnected by said toggle, and lost motion connections between said last named means `and said togglev con*v structed and arranged to prevent premature lowering of said work support. f e

14. In a machine of the class described, a work support, a iixed abutment, means for raising and lowering said work support int'o and out of position to` `clamp the work against said abutment, a stop arranged tok be moved into position beneath'said work support beforethe machine is started, and lost motion ,connections between said stop and said raising and lowering means. n

15. In a machine of the class described,

awork support, a treadle,-fa toggle for rais- -V operating connectionsfbetween said stop and lsaid treadle. 1 f

16. In a machine of the classdescribed, a work support, a toggle for raising and lowering said work support, a stop arranged to be moved into position beneath said work support when the worksupport is raised, and yieldingV lost motion Yconnections' between said toggleY and said stop yfor moving said stop into and out of operative p`osi tion. Y

17. In a machine or' the class described, a work support, atogglebyjwliich said work supportis raisedV and lowered, a stopl arf ranged t0 be moved into position beneath said' work support' when said toggle is straightened, said stop and said work sup.-

port being arranged to 4be brought into operativeengagement by a further movement of said to gle out of straightened position. 1 8.v n a `machine of the class described, a work support, a spring, means for raising and lowering said work support constructed to bring the pressure of the spring tov bear upon said workl supportwhen raised and to remove said pressure 4when said supportl is lowered, a. stopv `forV preventing kthe removal of the spring pressure when the work support' is raised, and lost motion rconnections between said raisingand lowering means and said stop for moving said stop into and out of operative position.

19. In almachine `of the class described, a vwork support, a treadle .for raising and iook lowering said work support, an abutment arranged to be brought into operative position beneath said work support when it is raised to lock it in raised position, and means connected to said treadle for yieldingly pressing said abutment toward operative position as the work support is being raised.

20. In a machine of the class described, a work support, means for raising and lowering said work support, a stop normally at one side of the lowered work support arranged to be moved into position beneath the work support when the work support is raised, and means connected to said raising means for yieldingly pressing the stop against the side of said work support as it is being raised.

21. In a machine of the class described, a work support, a toggle arranged to be straightened to move said work support into work supporting position and to be broken to permit said work support to move into work receiving position, other means arranged to be moved into position as said toggle is straightened to lock said work support in work supporting position before the machine is started, and direct lost motion connections between said last-mentioned means and said toggle so constructed and arranged that said toggle exercises positive control over said last-mentioned means.

22. In a machine of the class described, a work support, starting and stopping means comprising a treadle, connections between said work support and said treadle comprising a toggle arranged to be straightened by said treadle to move said work support into supporting position and to be broken to permit said work support to move into receiving position, means for limiting the movement of said toggle by said treadle, and means controlled directly by said toggle for preventing said work support from being lowered until said treadle has effected a partial return movement of said toggle.

23. In a machine of the class described, a `work support, starting and stopping means comprising a treadle, connections between said work support and said treadle whereby the work support is raised to apply final work-clamping pressure before the machine is started, means for thereafter locking said work support in work supporting position, and lost motion connections between said treadle and said locking means constructed and arranged to prevent unlocking of said work support before the machine is stopped.

24. In a machine of the class described, a work support, starting and stopping means comprising a treadle, positive connections between said work support and said treadle whereby the work support is raised before the machine is started, means for locking said work support in work supporting position, and lost motion connections between said treadle and said locking means whereby said treadle may be moved to stop the machine before said work support is unlocked.

25. In a machine of the class described, a work support, a spring, starting and stopping means comprising a treadle, a toggle arranged to be straightened by said treadle before the machine is started to cause said spring to act upon said work support, and means moved into position as said toggle is straightened for preventing the removal. of the action of said spring upon said work support before the machine completes its operation upon the work.

26. In a machine of the class described, a work support, a spring, means comprising a toggle and a member upon which one link of said toggle is pivoted for raising said work support and compressing said spring, a stop for preventing premature lowering of said work support having a pivot upon said member co-aXial with said toggle link pivot, and lost motion connections between said toggle link and said stop for operating said stop.

27. In a machine of the class described, a work support, starting and stopping means comprising a clutch operating means and a treadle, connections between said work support and said treadle comprising a toggle bv which said work support may be raised and lowered, connections between said treadle and said clutch operating means having provision for lost motion whereby said toggle may operate to raise said work support while said lost motion is being taken up, means for locking said work support in raised position, and connections between said treadle and said locking means having provision for lost motion after said iirstmentioned lost motion has been taken up.

28. In a machine of the class described, a work support, starting and stopping means comprising a clutch operating means and a treadle, connections between said work support and said treadle whereby the work support is raised by said treadle, connections between said treadle and said clutch operating means having provision for lost motion whereby the work support is raised before the machine is started, and means for locking said work support in raised position also so connected to said treadle as to be brought into operative position before Ythe machine is started.

29. In amachine of the class described, a work support movable between a work receiving position and a work supporting position, means operating upon said work support when in work supporting position for intermittently depressing said support to points between said positions to permit the work to be fed, means for moving said work support between itsV receiving and supporting positions comprising a toggle in the connections between said 'support and said depressing means, and Aother means for maintaining said work support in work supporting position.

30. ln a machine of the class described, a stationary abutment, a work support movable upwardly for pressing the work against tlie abutment, starting and stopping mechanism comprising' a treadle, and means operated from said treadle for providing a rigid support for the work support, said means being operative, after tlie application of the maximum work-clamping pressure and before the machine is started, for holding the work support in final work-supporting position.

3l. In a machine of the class described, a stationary abutment, a work support for pressing the work against the abutment, starting and stopping mechanism comprising a treadle, connections between the work support and the treadle constructed and arranged to cause the work support to be raised into `final work supporting position before the machine is started, and means also operated from said treadle for locking the work support in sain work supporting position, Y 32. ln a machine of the class described, a work abutment, a work support movable relatively to said abutment to clamp the work between the work support and the abutment, means for moving said work support to apply iinal Vwork clamping pressure,

' starting and stopping means, a single member for operating Said work support moving means and said starting and stopping means to perform the operations described, a stop for preventing Vpremature work-releasing movement of said work support, and means whereby said stop is controlled from said member. K

33, Iii-a machine of the class described, a work support, a spring, work support moving means constructed to apply the pressure of said spring to said'work support, a lever, positive connections between said lever and said moving means for operating said moving means, astop for preventing prematureV work-releasing movement of said work support, and lost motion connections between said lever and said stop.

34. In a machine of the class described, a movable work support, starting and stopping means comprising a treadle, connections between said work support and said treadle whereby thework support is raised before the machine is started, and means comprising a member arranged to be interposed in the path of the movable work support for locking said work support in work supporting position constructed and arranged in such a way that the treadle may be moved to stop the machine before ,the work support is unlocked.

35. In a machine of the class described, a work support, starting and stopping mechanism comprising a treadle, means for raising the worksupport to apply final workclamping pressure, and connections between said work support and said treadle constructed and arranged to provide a rigid support for the work support after the application of said pressure and before the starting of the machine.

36. In a machine of the class described, a work support, starting and stopping mechanism comprising a treadle, means comprising a toggle for raising the work support, said toggle being movable beyond center, and connections between said work support and said treadle constructed and arranged to provide arigid support for the work support after said toggle moves beyond center.

' 37. In a machine of the class described, a work support, starting and stopping mechanism comprising a treadle, means comprising a toggle for raising the work support, said toggle being movable beyond center, and connections between said work support and said treadle constructed and arranged to provide a rigid support for the work support, said mechanism being operative to start-the machine while the toggle moves beyond center. i

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE Gonnii. 

